Questions tagged [odds-ratio]

A measure of association between two binary variables equal to the odds of a 'positive' outcome in 1 variable divided by the odds in the other. The OR ranges (0, infinity). It has a strong connection to logistic regression.

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Can you adjust an odds ratio for covariates without having subject level data on those covariates?

I'm working on a research project and am trying to adjust an odds ratio for several covariates including sex, age, high/low socioeconomic status, and high/low disease comorbidity. I have the number of ...
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How do we interpret odds ration below 1 when the 95% confidence interval lies below 1? [closed]

I have done logistic regression and the odds ration got was below 1 and I have noticed that the 95% confidence interval for the effect estimate which I got lies below 1. The p-value is statistically ...
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Should I correct odds ratios for multiple testing and if yes, how?

I did I fisher test (2x3 table) and after a significant result I performed three separate fisher tests for the possible comparisions. I corrected the p-values for multiple comparisons, but in addition ...
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Cleaning up several crude odds ratios from several sources

Does anyone know a formula for pooling odds ratios across studies? I'm trying to do a quick pen and paper pooling of different numbers of odds ratios from different studies where I don't have the ...
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How to interpret factor predictor variables (+ interaction term) in ordinal logistic regression?

Within the ordinal regression formula I included the interaction term "factor(cityname)*suburb" with cityname taking either Edmonton, Halifax, Toronto, or Vancouver and suburb either 0 or 1 (...
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Why odds ratios cannot be higher than the stepwise betas?

I am performing a logistic regression analysis after performing a stepwise regression. I would like to know why the odds ratios of the logistic regression cannot be higher than the stepwise betas.
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Hazard ratio and relative risk (or odds ratio) in case of very few event/censoring times

As far as I understand relative risks and hazard ratios are very similar concepts (although this paper seems to disagree). The advantage of hazard ratios is the inclusion of temporal information. I ...
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Is this interpretation of odds ratios being multiplicative correct?

In a published paper (DOI 0011128713498330) an author claims something like this (slightly reworded to improve readability without the context of the entire paper): "As noted in the Results ...
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What is the intuition behind the odds scale?

What is an intuitive explanation of the odds scale? In a logistic regression such as $$logit(p) = \beta_0 + \beta_1 x$$ we often interpret $\beta_1$ by looking at the odds ratio, $e^{\beta_1}$, which ...
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Odds Against Success By Chance

If one can expect to be right 10% of the time, by chance alone, how do you determine the odds against being right 22% of the time by chance alone?
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How should I calculate effect sizes for a 2X4 table?

I have used the software SPSS to produce a 2X4 contingency table, using categorical data. I am aware that odds ratio is only applicable for 2X2 tables. Are there alternatives to odds ratio to try and ...
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Appropriate analysis of ranked and categorical data for swiss-system tournaments

I am looking for some advice and help on how best to analyse swiss-system tournament data (https://en.wikipedia.org/wiki/Swiss-system_tournament) In terms of my data, I have tournaments that happen ...
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is this odds ratio transformation correct?

I am using a function based on the r package stargazer to transform outcomes from a poisson analysis to odds ratio. I want to make sure that the output is correct, because I don't fully trust the ...
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Interpretation of continuous variable in an odds ratio for logistic regression

I have an odds ratio of 1.02 for x variable (Age, a continuous variable measured in units "1 year"). My response variable is Y. I would interpret this as for every increase in Age by 1 year ...
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Differences between P value and confidence interval for calculated OR

I have returned to a piece of work and was re-running some statistical analysis. I found differences in the P values (which is > 0.05) and OR confidence intervals which was greater than 1. Is there ...
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calculating relative risks and odds ratio

How do I calculate : "cc":relative odds of preemployment testing only among non-marijuana users, "dd":relative odds of preemployment testing & random testing among marijuana ...
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Breslow-Day vs. the Chi2 test for contingency table

Let's assume there are 3 experimental centres: A, B and C. At each centre, we check some percentage structure, X to Y, say X/Y*100% I want to check the heterogeneity across the centres. I was told to ...
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logistic regression - exercise odds ratio and probability of belonging

I have a question related to an exercise that is probably very easy, but I'm getting quite desperate with it. I would be very grateful if someone could explain me the solution. A logistic regression ...
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for fun: can I estimate prevelance in a local population based on global exposure-outcome meta analyses?

I have the RR of miscarriage if exposed to moderate alcohol during pregnancy = 1.8. I have a small population where 7% is moderately exposed to alcohol during pregnancy. How can I ESTIMATE how many ...
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Why multinomial regression gives huge difference in Odds Ratio when variable treated as continuous and tertile categories?

I am trying to perform a multinomial regression model with the values of Leptin against BMI levels (Normal, Overweight and ...
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convert accelerated time factor to odds ratio in accelerated failure time model

In the accelerated failure time model with log-logistic distribution: $log(T)= \gamma_0 + \gamma_1 Z_1 + ... + \sigma W$ In many R packages, SE and 95% CI are provided for $\gamma$, $\sigma$, or their ...
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stratified analysis - Mantel Haenszel?

I am trying to solve a problem about a case-control study, where I need to calculate the odds ratio the association of X and Y, stratified by two age groups. First, I calculated the crude OR for each ...
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How to find "P for trend" in logistic regression?

When I read some articles that used logistic regression, many of them report OR values (usually adjusted ones) plus the "p for trend." Usually, "p for trend" is put when presenting ...
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Condition logit model: Weighted mean of ratios of coefficients of subgroups does NOT equal the ratios of coefficients of the whole sample, why?

I am well aware that when one splits the sample into subgroups (e.g. sex, country, whatever), and then estimates any logistic regression model, the coefficients are not comparable between (otherwise ...
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Trouble replicating a simple OR table (Bayesian meta-analysis)

I'm reading this intro to meta analysis from Columbia University, and I cannot replicate the Log OR in the very first table. For the first study: OR = (1/39)/(2/34) = .03/.06 = 0.44 Log OR = log(0.44)...
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How to interpret a logistic regression model with negative coefficients of varying magnitudes and odds ratios <1?

I'm doing logistic regression where X has four factors (1-4) and Y has two factors (0-1). I did: ...
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Convert Odds Ratio to Raw Number for Meta-Analysis (using r)

I am conducting a meta-analysis. Most of the studies reported raw numbers for each group, but some reported only odds ratio with confidence interval. Is there a way in r that I can back-calculate odds ...
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Odds ratio for an $I \times J$ table

I am trying to find a general expression for the odds ratio in a two-way table. I know for a $2 \times 2$ table odds ratio can be expressed as: $${\rm OR} = \frac{\pi_{11}\pi_{22}}{\pi_{12}\pi_{21}}.$$...
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Flipping odds ratios from a fuly adjusted regression model

I want to be able to rank odds ratios within and among predictors. Some of the odds ratios are less than 0 and some are greater than 0. Is it legitimate to flip the ones that are less than 0 by ...
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How can I calculate the variance of the log odds ratio for meta-analysis with multiple trials per participant?

Background I am performing a meta-analysis of priming studies, where participants receive one of two primes and then produce one of two responses. In these studies, each participant completes multiple ...
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Choose statistical test method: comparing the frequency of a disease (only interested the disease post-procedure) in 2 groups of patients

I am working on 2 groups of patients, group A and group B. The patients in both groups have received a same procedure. We have observed the patients before and after the procedure. Suppose there is a ...
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Log Odds in Zero Noise Limit

I have the following problem: Define $p := 1 - \exp(-\exp(-\lambda^2/2\sigma^2))$ and consider the log odds: $$\log \frac{p}{1-p} $$ I'm interested in the limiting behavior as $\sigma^2 \rightarrow 0$....
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odds ratio from Xgboost

I am using a Xgboost for a classification problem. The output is binary {0,1} and some of the input variables are categorical while the others are continuous. I would like to know if it is possible to ...
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Do Odds Ratios (OR) have a similar ranking categorisation as Cohen's conventions?

I'm trying to meaningfully interpret the findings from this meta-analysis which states: "Additional evidence supported the association between fever during pregnancy and increased risk for NDD in ...
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Problems creating odds ratios for a binary regression in R

I am creating a binary logistic regression in R studio. So far I have performed the regression and I am trying to convert it to odds ratios using the function: ...
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Combining Time-Defined Hazard Ratios and Odds Ratios in Meta-Analysis

I am attempting to complete a meta-analysis of studies that variously report Odds Ratio of death at 30 days, and Hazard Ratios for death at 30 days. All are reported as being close to 1 (range 1.2-1....
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Coefficients interpretation in rare events case - Logistic regression

So, basicaly, me and my team are trying to target our marketing campaigns based on logistic regression's coefficients. The idea is to understand the dimensions that increase or decrease the ...
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STATA: Create Dataset from Contingency Tables for Statistical Interaction [closed]

I have three contingency tables for a case-control study: the crude 2x2 table with exposure and outcome: ...
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Restricted Cubic Spline Function Summary Intepretation

I am trying to incorporate spline transformation into my logistic regression and finally piece together the following (working) R code (pls see it below). However, I have no idea how to interpret this ...
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Spline-transform regression - concept clarification

I am learning spline transformation and am confused about several concepts. Any guidance is all appreciated! Am I understanding this correctly: I should only spline-transform my continuous predictors ...
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Compare Odds ratios between two logistic regression models with same IVs and same sample but different DVs (SPSS)

I would be very pleased if someone could comment on my issue as I have not yet found a way to do this. Basically, what I am trying to find out is a way to statistically compare the Odds ratios of the ...
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Binary predictors with very wide 95% CI in the Logistic Regression

When I fit a binary predictor in the logistic regression model, I got a high odds ratio and a very wide 95% CI (e.g. OR=11, 95% CI [1.5-229.5]; p = 0.041). My binary predictor is smoking status and my ...
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Interpreting logistic regression in R with huge OR: Strategies to interpret

My dataframe looks like this -> dput see at the end: ...
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How to get odds ratio from regression analysis when the response variable is continuous variable

I want to use odds ratio for interpreting the association between indepednet variales and response variable, but my response variable is continuous variable. I don't know what analysis to do for ...
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Should I use EXP(confint(.)) or Delta method to calculate CI in Meta analysis?

I have a population in which I want to calculate the odds ratio and its CI for the treatment/outcome, calculations of the CI using the exp(confint) in R and the delta method provide slightly different ...
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Odd's Ratio and Probability Contours

I am trying to better understand the concept of the Odd's Ratio. I found this example that explains this concept along with a visualization: The above example demonstrates the use of the Odd's Ratio ...
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odds ratio and logistic regression

I use the following code to fit a logistic regression to see the effect of status on error rate: ...
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How to calculate odds ratio of continuous vs binary variable?

I'm trying to understand the statistics done by someone who I can't reach. The study is about enuresis in small children. The enuresis variable is binary (1 or 0, or the child usually wets the bed at ...
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Convert cumulative incidence proportion to odds ratio and forest plot

I have a table with cumulative incidence rates (36 mths) of an event stratified by different variables. E.g. var1 - 2.9%(2.4%, 3.4%) var2 - 9.4%(8.2%, 11%) etc. ...
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convert the ATE Average Treatment Effect from a doubly robust model into Odds Ratio

How would one convert the ATE Average Treatment Effect from a doubly robust model into Odds Ratio? Or is it better to discuss this by converting into risk ratio? If so, how is this done.
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